An obligate parasite, or holoparasite, is a parasitic organism that cannot complete its life-cycle without exploiting a suitable host.
Part of the Andes mountain range, Aconcagua is the second highest of the Seven Summits, behind only Mount Everest in Asia. At 22,837 feet (6,961 meters), not only is it the highest mountain in South America, it is the tallest peak in all of the Americas as well as the Southern and Western Hemispheres.
Mt. Whitney at 14,494 ft. (4,418 meters) located in California is the tallest mountain located west of the Mississippi River. The 2nd highest peak is Mt. Elbert, located 10 miles southwest of Leadville, Colorado. It stands at 14,433 ft. (4,399 meters).